Oil-well under reamer



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v NVENTOR. vlbor L. Conaqhcm ATTORNEYS.

' V. L. CCNAGHAN oIL WELL UNDER EAMER Filed March a, 1925 Patented @et 16,1923.. y

',vioroa' ij; ooneerran, oi" wioirire, Kansas. e

oir-WELL; minne. BVEVAMER .Y sppueationfaied March 8,1923? seriaijnaezaeez.'

To ir/ZZ whom t may concern; v Y Be it known that I, Vioronll. CoNAGHeN, a citizenoic theV United; States, residing at Wichita, county ofSedgwick, and State oi:V Kansas, have invented certain new and Auseful Improvements in Oil-Tell Under Reamers, of vwhich the following Vis a specifica-V tion, reference being had to the accompanying drawings, which form Aa part o this application. t

My invention relates to oil'wellA adjustable'under reamers. Y

The objects of my inventiornlare as Jfollows; Y A

First; To provide aV detachable instrument, that can be let down bythe drilling rope Vand manipulated in anf'upwardfand* downward movement. v ,Y .7

Second; Tor provide a mechanism lwith concealed tensioning devices.

AThird; To provide anfunder reani'erwhose cutting bits-will contract to the insidediame-ter of the casing and expand immediately when passing through and out at the end of the casing. f J

Fourth; An under-reanier with .rezrpansive-` bits that will draw back in the end of the casing and automatically. contract tothe diameter ofk the easingv without catching on the end'ot said casing.

Fig. l is an elevation of the mechanism.Y

without being connected to kthe eable .k Fig.' .2 is an end view showing the bits expanded. Fig. 3 is a partial sectional view through the she-ll inclosing the core to which is attached the reamingbits. Fig. 4.- is a detailed viewpof the core.

l is` the threaded portion of the; shankf2,

saidshank having a squarel portion 3 to* which is applied a wrenchk `for convenience to remove a connecting member which is socketed and threaded to receive the thread' ed portionl, the said conneetion'being-attached to acable which extendsv 'frointhe derrick down. The connecting member, cable and derrick are knot shown in the drawings, except the connection and ropein Fig. 8. 4 is Vthe shellV which is keyed to the core 5, by means of a key 6, which passes throughl FiggfS is a view arectangularsquare 7 through' the shell and lthe neckof thecore, said vopenings registering with eachother. The shell 4l and the Vshank 3 areintegraland the lower end of said shell is notched to receive the. shoulder core Sillas a shank 8, said shank is adapted key is tlieeonvenie'nt means for holding said core in thelshell while in operation, but

the force oi the process of under reainingk will have its bearing at 9 and 10 and also atthe shouldersll onshearing bit 12, said shoulder contacting the shell at 13. The core 5 ishoused to receive the shank lfl'of the under roaming blade at l5 and the conshown in Fig. 5. At 17 is shown a spreading meinberfunctioning as a cam to expandlv the cutting edges lS-of thebits lf2. i9 is a connecting rodh'aving a ball vE20, said ball adapted to engageV in a socket 2l, and on said rod is placeda tensionspring 22, said' spring adapted to tension on shoulder 23 and 'against a head 24 on said pin. The rtension of said springallows thev cutting bits to contract under tension when entering the oil My experience in oil well drilling has been that at times there are occasions when the metal easing Afor the oil well, should be lowered and asia rule in the Vprocess of drill-' .ing with the ordinary gravity drill, the hole below the easing is smaller in diameter than the hole equal to, or larger Athan the casing, after wliich'itis possible; to lower the casing tothe point desiredy and add sections to theftop as lowered.V`

of the vunder roaming blade. `The g to engage on the bottom of shank 3 andthe `ne-:ztingrod and spring are housed at 16 as 'well casing and also'assistsinexpansion of vthe cntting ends of said bits as required for n enlarging the'hole below the casing.

that of the casing and should the 'formation 'be a. ,hard substance it is necessary to ream To operate myV device a'reonnection is at- Q .taehed tothe steel cable vandsaid connection .'s adapted vtoscrew tightly` on the shank of myY under reamer, and then by pressing the shearing blades togethen: it is entered into the casing and then 'lowered to `the depth where it passesV throughthe casing-and 1mmediatelytheshearing blades are tensioned outward by the y springs and connections fheretoforedescribed, contacting the walls of the hole, then by an 'upward anddownwal'd-y movement, the blades will shear 'the sidek walls' enlarging its diameter. Such Hmodi,-

cations may be employed in all parts of the mechanism as lie vWithin the scope of the appended claims;

Having thus described my invention,

What I claim as new and ,desire to secure by Letters Patent is;

Vtensioning means and shearing bla-des attached thereto, Jfor the purpose set forth and described. v Y

2. In oil Well under reamers, a shell, having a shank, With threaded means for venscribed.

gilgng all Operating connection, said shell i i being notched at the opposite end in whichV shearing blades engage, a core, having a plurality of housings about its periphery, said housings having bearing shouldersformed therein tor function as spring `seat bearings,

a shank on theend of -said core to engage against the bottom of said shell, a cam member on the opposite end of said core tolfuncblades and a plurality of shearing blades Vand pivotedly connecting rods, a spring on said rods, to functionv as tensioning means, to expand the shearing blades to a flarin position, for the purpose set forth and devio'roa'n CONAGHAN.

tion as expansion means for saidshearing 

